System for acquiring data from facilities and method

ABSTRACT

A field instrument and system for obtaining pressure, flow and temperature data from a facility. The field instrument includes an enclosure having an opening therein. An integrated analog sensor is sealingly contained within the opening. The field instrument further contains an external analog sensor. An analog to digital converter converts the analog signals to digital readings. An external digital sensor is also provided, with the digital output being communicated through a second opening within the enclosure. A control member that receives, stores and processes the digital readings is positioned within the enclosure. A communication module is included to transmit the digital readings to a remote computer. The communication module allows for two way communication between the field instrument and remote computer. The remote computer may be a server that allows for access by many users. The communication module also allows for locally accessing the digital readings via a serial port to a local terminal.

This is a continuation-in-part application of the patent applicationfiled 13 Jan. 2000 as Ser. No. 09/482,415, entitled “System forAcquiring Data from a Facility and Method”.

BACKGROUND OF THE INVENTION

This invention relates to a system for obtaining pressure, flow andtemperature data from one or more facilities. More particularly, but notby way of limitation, the invention relates to a system having one ormore instruments that collect, process and store measurements ofpressure, flow and temperature and relays data to a remotely locatednetwork data receptor series, where for example it may be accessed bymultiple users.

In the production of oil and gas from subterranean reservoirs, operatorshave found it necessary to complete wells in many remote regions. Inorder to produce, transport and refine hydrocarbons, it is necessary toconstruct production facilities at these remote regions. Due to thehazardous nature of hydrocarbons, it is necessary to employ varioussafety features in all phases of the process to ensure againstpollution, explosion, and other safety hazards.

Operators find it beneficial, if not necessary, to monitor pressure,temperature, flow rates, etc from these oil and gas facilities. Thereasons for monitoring are numerous. For instance, the operator may wishto test the producing well in order to calculate bottom hole pressure,permeability, skin damage, etc. Additionally, the operator may simplywish to monitor the pressure within separators, pipelines and/or vesselsto maintain proper working conditions. Regardless of the specificapplication, there is a need to accurately monitor conditions at the oiland gas facility in a timely manner.

It is furthermore desirable to provide a system for the monitoring ofconditions at a number of individual oil and gas facilities, which maybe geographically spread over a given region, to permit a broadassessment of overall conditions in the production facility or region.

Prior art devices have been designed to remotely communicate with oiland gas facilities. For instance, Supervisory Control And DataAcquisition (SCADA) systems have been developed to monitor andcommunicate with these remote areas. However, these SCADA systems sufferfrom a variety of deficiencies.

A significant deficiency is related to the inherent limitations of theMaster-Slave communication protocol that is employed by SCADA systems.The Slave must be always powered-up waiting for the call from theMaster. And when the Master calls, the Slave must immediately respond tothe Master to minimize the time Master spends with the Slave.

Further, prior art systems communicate from a limited number of oil andgas facilities to a single monitoring station which in turn relaysinformation to a central control station. This architecture is necessarysince the Master monitoring station must poll each Slave Field locationindividually to prevent communication collisions.

Another limitation in current practice is the accuracy of pressuremeasurement, which is impaired by ambient temperature fluctuations. Thisaccuracy limitation reduces the effectiveness in many process monitoringapplications that depend on measurement stability, such as processsimulation or process accounting.

A further limitation of current practice is the elaborate installationrequirements that result from the physical size, number of componentsand complex interconnections that are needed to implement each fieldlocation with a remote measurement system.

Therefore, there is a need for a system and method that can capture,store and process accurate pressure, flow and temperature data, andcommunicate this data in a more flexible manner to a local computerand/or remote server. There is also a need for a system that will allowfor users to access data from multiple remote locations on an as neededbasis. Further, there is a need for a system that can alert remote usersof predetermined alarm conditions in an efficient and timely manner.There is also a need in many practical applications for improvedpressure measurement accuracy and stability compared to what is achievedusing current practice. There is also a need for an instrument that canwork in an oil and gas environment without fear of explosion. There isalso a need for an instrument that integrates many of the measurementsystem components into a single, compact package to simplifyinstallation. These, and many other needs, will be accomplished by theinvention herein described.

SUMMARY OF THE INVENTION

The system of the present invention may incorporate one or more fieldinstruments, which are used to collect and transmit data signals fromremote locations to a central server. The field instruments could be ofthe same or differing construction and could be adapted to collect andtransmit data respecting a number of operations, conditions, includingwithout restriction oil and/or gas flow rates, pressures, temperatures,production byproduct gas concentrations and the like.

In one possible aspect, the system for transmitting a pressure readingobtained from a process line is disclosed. The pressure reading systemcomprises as a field sensor instrument, one or more small, explosionproof enclosures having a first opening with a first integrated analogpressure sensor therein which is connected to control means forreceiving, processing and storing the digital pressure output readings.The control means is located within the enclosure. A second remotedigital sensor is connected to the control means via a second openingwithin the enclosure. The system may further comprise means, positionedwithin the internal chamber, for transmitting the digital pressureoutput readings to a remote location. The system also contains serialcommunication means for transmitting the processed digital pressureoutput readings to a terminal located at the facility.

In one of the embodiments, the system includes database means,operatively associated with the transmitting means for transmitting toeach field instrument, for storing the digital readings with thedatabase means and allocating the stored digital readings to theindividual instrument and/or facility, including a data manager meansfor receiving, retrieving and communicating the digital readings. Thesystem may further comprise a central server, located remotely from thefacility, and wherein the central server is capable of receiving thedata.

The system may further comprise a field instrument having user interfacemeans, operatively associated with the database means, for allowingaccess to the data, and a user computer having means for accessing theuser interface means.

The system further comprises a plurality of analog sensors producing ananalog signal; an adapter connected to the analog sensor, with theadapter being sealingly received within a second opening in theenclosure; and means, electrically connected to the analog sensor, forconverting the analog signals to digital readings.

In one of the preferred embodiments, the transmitting means comprises acommunications module means for transmitting the digital pressure outputreadings using a TCP/IP protocol to a central server via the Internet.The system may further include a user computer, and wherein the usercomputer has loaded thereon a web browser capable of reading the dataand a communications link from the user computer to the Internet.

Although the enclosure is disclosed as housing pressure sensors whichare used in sensing pressures, it is to be appreciated that other typesof sensors could also be used. For example, temperature sensors and/orchemical sensors could be similarly housed within the field instrumentenclosure, in place of, or in addition to the pressure sensors, for usein providing additional sensor data at a given facility.

A process for collecting, transmitting and monitoring data such as apressure from one or more facilities is also disclosed. The processcomprises communicating the pressure to a tubular member andcommunicating the pressure from the tubular member to a pressure sensorat a given ii facility. In a preferred embodiment, an enclosure isprovided, with the enclosure having a first opening, a second opening,and an inner chamber, and wherein the pressure sensor is housed in thefirst opening.

The process includes sealing the first opening and the second opening sothat the pressure is withheld from the inner chamber so that thepressure is precluded from entering or exiting the inner chamber. Adigital pressure reading from the pressure sensor is collected andtransferred to a control means for receiving, processing, and storingthe digital pressure reading, and wherein the control means is locatedwithin the inner chamber. Next, the digital pressure reading in thestorage means is transferred to a modern communications means forcommunicating digital data, and wherein the modern communications meansis located within the inner chamber.

In one of the embodiments, the digital pressure reading is converted toa digital packet data in the modern communications means which in turnis transmitted via the modern communications means. The digital packetdata is received at a remote data base engine where it is stored forlater retrieval. The process may further comprise collecting an analogreading with an analog sensor, and wherein the analog sensor issealingly housed within the second opening of the enclosure. The analogreading is converted to a digital reading and is transmitted to thecontrol means.

In one of the embodiments, the data base engine contains a data managerand the method further comprises storing the digital pressure data anddigital temperature data for each facility. Additionally, the databaseengine may further contain a central server interface and the processfurther comprises providing a central server communicated with thedatabase engine via the central server interface and accessing thecentral server from a user computer. Next, the digital pressure readingfor a given facility is requested from the user computer and the digitalpressure reading is transmitted to the central server which isultimately transmitted to the user computer.

According to the teachings of the present invention, it is also possiblefor a user computer to have a direct link to the control means. The usercomputer could be located at the facility or at a remote facility. Theprocess would comprise connecting with the control means from the usercomputer with the direct link, and transmitting the digital pressurereading to the user computer.

In another embodiment, the process includes polling the fieldinstruments data and setting predetermined data limits. Once apredetermined limit is exceeded, this exception will be recorded, and anexception signal is produced. The exception signal is sent to thedatabase. The exception signal is transmitted to the central server andthen transmitted to the user computer.

The process may also include sending the digital pressure data to a webserver and then sending the digital pressure data to the Internetwherein the digital pressure data may be accessed over the Internet witha web browser from a user computer.

In one of the preferred embodiments, the step of correcting the digitalpressure data for ambient temperature effect corruption includes mappingthe digital pressure data through iteration and back calculating to ahigh accuracy pressure reading.

A feature of the present system includes allowing for routine andunattended measurements, data logging and compression and data basegeneration locally and remotely. It is possible for long term processperformance monitoring, on-board configurable process analysis (i.e.report when a process parameter reaches a certain value), and processmonitoring and indication.

The operating system has incorporated therein orifice gas flow AGA 3 orAGA 8 calculations, process excursion reporting and time stamping (i.e.for peak demand billing), and warning generation and error logging (i.e.for process interlocks and diagnostics). The operating system performssampling at rates fixed, programmed sequences, or is triggered and/orauto adjusting. The sampling rate may be based on a pressure set point(rise and fall), the rate of pressure change (rise and fall), thepressure differential (rise and fall), a temperature set point (rise andfall), and the rate of temperature change (rise and fall).

The sampling rate may also be based upon calculated parameters such asflow rate (i.e. high flow, high sample rate), rate of flow rate change(i.e. steady flow, low sample rate, erratic flow, high sample rate). Itis possible to have a sample rate related to the state, the change ofstate, the period or the rate of a digital input signal. Another featureis the ability to perform dynamic and/or static source characterizationthat includes in-line testing for pipelines, pumping stations, tankfarms, etc that need transfer function characterization as well as welltesting. For instance, the instrument can be used with shut-in tools todevelop “Pressure vs. Time” and “Pressure vs. Flow Rate” characteristiccurves for reservoir analysis. The system can also be used forpreventive maintenance reminders and system error detection andflagging.

Data transfer and alarm notification capability of this system issignificantly more flexible than prior art devices because of the use ofTCP/IP protocol. Data transfer and alarm notification capability of thissystem is significantly more flexible than prior art devices in partbecause the field instrument, in one preferred embodiment, can initiatea communication to a central location within the functionality of theapplication layer protocol of the system. For example, instead ofwaiting until an instrument is poled from a remote master as in theprior art, the system and protocol of one embodiment of the presentinvention permits the field instrument to decide whether to initiatecommunications, such as if the field instrument has detected an alarmsituation, and supports this data transfer and notification. Thisflexibility over the prior art devices improves communication within thesystem, and, can result in more robust alarming. The system will alsoallow long term data logging and storing of this data. Perhaps mostimportantly, these instruments have high accuracy, high precision andhigh resolution of pressure data which is essential for propermanagement and optimization of oil and gas production and transportfacilities.

With reference to external communications, the system allows forcommunications port management. Additionally, the wireless modern optionallows for access to dedicated or local public phone systems orsatellite access for very remote locations, which in turn allows accessto the Internet or local intranet. The instrument can use either anintegrated or remote antenna.

The system data management and data routing features may be configuredin various ways. The simplest is a one-to-one relationship where datafrom one instrument is conveyed to a single user. Instrument and dataaccess is managed by a single user. Second, it is possible to have datacollected from many instruments collated and conveyed to a single user.Instrument and data access is managed by a single user. Third, data frommany instruments is collected, collated, and conveyed to one or morepreferably a variety of users. Instrument and data access and controlprivileges are managed by a localized or distributed process and may bedifferent for different users.

An onsite user has a local display and indicators that include liquidcrystal display (LCD) for presenting measurement results, error codesand message; a light emitting diode (LED) indicating instrument statusand a power LED. Manual input switches are included for master reset andsystem configuration. Also, the local terminal option allows for runninglocal diagnostics, install firmware upgrades and possible localretrieval of process data.

Another instrument feature of the preferred field instrument enclosureconstruction is that it is compact, relatively self contained, andhighly integrated. The enclosure can be used in hazardous locations (itis explosion proof, and rated for Zone 1). The enclosure is physicallyrugged and environmentally sealed.

Applications include fluid or gas metering, typically in remoteprocessing facilities or pipelines. The field instruments arecomparatively low cost and easy to install. Few changes are required toexisting facilities.

The system can monitor pressure and flow rate when the instruments arecombined with orifice plates. The operating system can instruct theinstrument to sample data at rates of up to once per second to enablehigh temporal resolution flow calculations to be performed. Theinstrument is suitable for custody transfer applications, point-of-usemetering, and transmission pipeline leak checking. The instrumentnormally acts in a remote data dump mode to periodically deliver loggedflow data and flow statistics to a user's database via a wirelessdigital modern. If required, the instrument can switch into an alarmmode to proactively signal that a process variable or state is out ofspecification or it can be periodically interrogated to read processconditions. The location of the device may be the well head, pipelinemonitoring station etc. Generally, communication will be over a wirelesscommunication channel provided either by a terrestrial cellular serviceor a digital satellite link. The novel instrument can be used in remoteand/or unattended settings or when accurate collection and time stampingof flow rate and totalized volume is required.

The system has multiple uses. For instance, the system can be used onoil and gas platforms, pipeline and pipeline facilities. The system canbe used to monitor water production and water table levels. The novelsystems can be used for custody transfers, or for monitoring storage anddistribution facilities, chemical processing facilities, bulk transferfacilities (trucks, ships, rail cars, etc.) Additionally, the fieldinstruments may be used on point of use systems and utilities includingwater and sewer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic flow chart of the basic components of the surfacedata system.

FIG. 2 is a cross-sectional view of a pressure data probe embodiment.

FIG. 3 is a schematic diagram of the hardware configuration of thepreferred embodiment.

FIG. 4 is a schematic flow chart of a first systems architecture of thepresent invention.

FIG. 5 is a schematic flow chart of a second systems architecture of thepresent invention.

FIG. 6 is schematic diagram of one embodiment of the server arrangement.

FIG. 7 is a flow chart of the digital signal processing of the presentinvention.

FIG. 8 is a flow chart of the analog signal processing of the presentinvention.

FIG. 9 is a flow chart of the sequence of powering the sensors in orderto take readings.

FIG. 10 is a schematic illustration of an enclosure of the presentinvention.

FIG. 11 is an operations and data flow chart of the preferredembodiment.

FIG. 12 is a schematic diagram of the hardware architecture of apreferred embodiment.

FIG. 13 is a schematic illustration of a system architecture of afurther embodiment of the present invention.

FIG. 14 is a conceptual flow diagram illustrating the general overviewof the architecture of the server/data base system and the flow of datain the system, according to one preferred embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIG. 1, a schematic flow chart depicting the basiccomponents of the field instrument 2 (FI) of the present invention willnow be described. In a most preferred embodiment, the FI 2 is a veryhigh accuracy pressure instrument designed specifically for use in theoil and gas industry. In the embodiment shown, two analog pressuresensors 4, 6 will be included within the enclosure.

The sensor core is a high accuracy, silicon crystal, strain gauge whichhas been laser welded into a high pressure autoclave fitting adapter,which in turn is threaded into one of the housing ports located on theenclosure. This sub-assembly is rated for pressures up to 12,000 psi,and has an over-pressure rating of 1.3. Suitable pressure sensors 4, 6are commercially available from Z. I. Probes, Inc. located in Canadaunder the mark # 14095140 Pressure Sensor.

An auxiliary analog sensor port is included in the enclosure to attachto a low accuracy external resistive based sensor 8, such as atemperature probe. Temperature probes are commercially available fromOmega, Inc. under the name PR-12 Type. The FI 2 may also incorporate anauxiliary digital sensor port 9 so that the device may attach tocommunicate to a number of external digital sensors over a RS-485signaled bus. On this bus, the FI 2 will poll external digital sensorsusing various protocols (i.e. Mod-bus). The enclosure of the FI 2 isexplosion proof, and will be C.S.A./UL certified for operation in Zone 1(Class I, Div 1, Group C, D, etc) hazardous locations. The actualenclosure will be described later in the application.

In the preferred embodiment, the FI 2 is self-powered by an internalbattery pack 10, even though the teachings of the present inventioninclude use of a possible external power source. A rechargeable batterymay be used. The rechargeable pack may be replenished by connecting asolar panel or with an externally powered charger as is understood bythose of ordinary skill in the art.

Readings are acquired on a preprogrammed time interval via a customoperating system 12 and stored internally in non-volatile memory 14.Between readings, the electronics and sensors are powered off toconserve energy via a preprogrammed routine in the operating system 12.The custom operating system utilizes a Real Time Clock (RTC). This RTCpowers up the system at the preprogrammed time and then interrupts themain processor 16 in preparation for acquiring each new reading. Oncethe electronics have been initialized, the processor 16 will acquirereadings from each of the internal sensors 4, 6 and external sensors 8,9 connected to it, and store these readings in non-volatile memory 12.The operating system 12, memory 14 and micro-processor 16 are referredto as the control means for receiving, processing and storing the data.

Once the readings are processed, they will be optionally displayed on asmall LCD 18 that can be viewed through a window in the enclosure aswill be described in greater detail later in the application. Alongsidethe LCD 18 there are also several small switches on the circuit board(not shown) to start an existing program, to reset the processor 16, andto manually configure the FI.

As will be detailed later in the application, the FI 2 can be utilizedto measure a variety of process points. For instance, the system can beused for the following: to measure a single pressure and singletemperature; to measure two pressures and a temperature; to measureorifice gas flow (which would require measuring a differential pressure)and a temperature. This list is illustrative.

In one of the embodiments disclosed, the FI 2 can be used in thewell-testing market. Thus, the invention allows for the monitoring of apressure build-up test. A line communicating a pressure from anyspecific well can be communicated with the pressure sensor 4 which willallow for the recording and transmission of data. The FI 2 can beinstalled onto a well head or pipeline for a short term test or for along term test. The readings thus collected may be stored in thenon-volatile memory 14 or communicated by one of the other describedcommunication means.

One of the advantages of the present system is the multitude ofdifferent operation modes. One mode would allow the readings to bedownloaded to an on-site computer after a test, such as a standardlaptop computer where they are viewed and a report is generated. Thismode of operation is termed “Memory” only.

According to the teachings of the present invention, the FI 2 has alsobeen designed with an internal wireless communications module 20. In thepreferred embodiment, the communications module 20 is commerciallyavailable from Sierra Wireless Inc. under the mark SB300. Field unitswith the communications module 20 require external power of about 3Watts, which will recharge the battery 10.

Once installed on the test site, the FI 2 will be self-contained and maybe left for long periods at that location. In the mode of operationutilizing the wireless communications module, the FI 2 can relay processinformation on demand from the host server, on a regular schedule or byexception reporting (i.e. exceeding an alarm threshold which will bedescribed later in the application). Once the raw readings of thesensors 4, 6, 8, 9 are acquired, these readings are converted to processvalues. This is done using an algorithm and a calibration (CAL) file.

The module 20 that has been packaged into the FI 2 is a low power devicethat allows computer to computer communication by at least one or moremeans, namely: (1) land-line phone; (2) circuit switched cellularchannel (i.e. it works on first generation analog cell phone channel);(3) cellular digital packet data (CDPD); and, (4) satellite (i.e. datamay be transmitted by utilizing low power satellite communications).These four standard means of communication allow the FI 2 to be locatedwherever. In one of the embodiments, the operating system 12 inconjunction with the communications module 20 will allow the FI systemto utilize the Transmission Control Protocol/Internet Protocol (TCP/IP)for all communications with the network architecture for all operationsincluding, but not limited to, well testing and monitoring applications.

TCP/IP is a major communication protocol standard. TCP/IP is actuallytwo separate communications of protocols working in conjunction. Anentire family of related protocols is covered in the TCP/IP heading,with TCP and IP as the two main protocols. TCP is partly responsible forbreaking data down into packets, as well as reassembling them. The IPpart handles how the data packets are transmitted over the network. Byusing TCP/IP, different computers running in different operating systemscan communicate with one another if they all obey this protocol.

As those of ordinary skill in the art will appreciate, the field levelSupervisory Control And Data Acquisition (SCADA) systems use amaster-slave based communications protocol (e.g. Modbus). In most fieldmonitoring situations, the remote office computer is typically theMaster and the field unit is the Slave. This inherently determines howdata flows from the field unit back to the office because the Slave canonly transfer information to the Host when it is polled. This means thata field unit cannot initiate a notice to the central office when it hasan alarm condition.

Using the application layer protocol, discussed in more detail below,the Master-Slave relationship of the prior art can be removed to allowfor information to flow asynchronously between the field unit and thecentral office. This novel system includes the following advantages overthe prior art: first, the field unit can notify the central officewhenever there is an exception or alarm condition without waiting forthe host to poll for it; second, packet based transmission over thewireless network removes the possibility where the field unit radio maymalfunction and jam the transmission link for all other units in theline of sight area; third, FI units may be activated to takesimultaneous readings on an array of sites. This list was meant to beillustrative.

Referring now to FIG. 2, a schematic illustration of a basic pressuresensor 4 will now be discussed. It should be noted that like numbers inthe various figures refer to like components. Generally, semiconductorbased pressure transducers are commercially available from companies IIsuch as National Semiconductor, Motorola, and Honeywell. The pressuresensor 4 of the preferred embodiment, commercially available from Z.I.Probes, Inc., has been modified by incorporating a temperaturecorrection factor algorithm into the operating system. In one of theembodiments, the sensor 4 consists generally of a flexible silicondiaphragm 30 with resistive bridge sensors 32 mounted on the surface.One side of the diaphragm faces a sealed chamber 34 while the other sideis made open to an input pressure. Deflection of the diaphragm in turncauses the resistive sensors to produce a signal as is well known in theart. All of the necessary electronic circuitries 31 including the bridgecircuit, excitation, instrumentation amplifiers, and other compensationand conditioning circuitry are included.

FIG. 3, which is a schematic diagram of the hardware configuration ofthe preferred embodiment, will now be described. The power managementmeans 50 includes an internal rechargeable cell 52, which in thepreferred embodiment is a Lithium (Li) and/or lead-acid basedrechargeable battery. This battery 52 is suitable for an ambienttemperature range of −20 degrees C. to +50 degrees C. Some of thefeatures of the power management means 50 will also include batteryprotection circuit (not shown) which allows for low voltage shut downand protects the battery from deep discharge degradation effects. Alsoincluded will be a high voltage clamp that protects the battery fromovercharge. Also included in the power management means 50 are circuitsfor battery cycling and conditioning that ensure that the batteries donot remain at peak charge voltage for extended periods. Smart chargertechnology is also included that is configurable to allow changes fornew battery technology.

As seen in FIG. 3, the hardware configuration also includes externalpower options. An optional solar panel connection 54 may be included.The design also allows for an optional battery bank 56 to beelectrically connected to the power management module. Additionally, amain adapter 58 can be included, with a Universal AC main converter toan intrinsically safe 12 VDC output. The hardware configuration includesan auxiliary power output 60 that is current limited, voltage limited,short circuit proof and ESD (electrostatic discharge) protected.

The hardware further comprises microcomputer supervisory functioncircuits, generally represented by the numeral 62. The circuits 62contain a real time clock which is designed to produce interrupts toinitiate samples. The circuits 62 also include micro central processingunit clocks that have features of full speed, reduced speed and halt.The circuits 62 further have a power supply monitor, watchdog timers,and system reset functions. The reset functions include resetting onpower activation or power interruption, and resetting on certainrecoverable system faults.

The microcomputer 64 includes memory storage means that contains theStatic Random Access Memory 66, non-volatile Read Only Memory 68,Electrically Erasable Read Only Memory 70, and Flash cache memory 72.The memory means will be electrically connected to the microprocessors73 (there are 2 processors; the high level microprocessor forcomputation intense work and the low level for on-going data collectionand reduced power consumption) for interaction as is well understood inthe art. The SRAM 66 is commercially available from NEC Co. under thename/parts number UPD431000AGZ; the ROM 68 is commercially availablefrom ATMEL Co. under the name AT29C020A; the EEPROM 70 is commerciallyavailable from ATMEL under the name AT28C256; and, the Flash memory 72is commercially available from AMD under the name AM29F032B. Themicroprocessor 73 is commercially available from NEC Co. under the name(High Level processor) Upd70f3107agj-uen, (Low Level processor)Upd78f9026agb-8es.

A local RS-232C 72 serial port is incorporated into the design thatallows for terminal connection detection, port configuration andinstrument configuration via a local terminal such as a laptop computer72 a. A Universal Asynchronous Receiver Transmitter (UART) 74 that has aport configuration and means for hardware handshaking is electricallyconnected to the RS-232C. The UART is commercially available from EXARCo. under the name XR15C850CM.

A RS-485 serial port 76 is incorporated with proper port settings,hardware handshaking means, and provisions for access to smart sensorsand process devices. The RS-485 port allows electrical connection tosmart devices such as the digital sensors previously described. TheRS-485 port is also electrically connected to a UART 77 which in turn iselectrically connected to the microprocessor 73.

Indicator and display means 78 are included which in the preferredembodiment may be a LCD. The LCD is suitable for graphics, digits, etc.to provide rudimentary process data display, setup guidance and errorreporting. It is possible to use Light Emitting Diodes (“LED”) whichemit green, yellow, and red light as “Okay”, “Warn” and “Fail”indicators.

Manual input is possible via the manual input module 80 which can bepush buttons [under cover] for master reset, simple set up, displayconfiguration, etc. A digital input capture port 82 is included that canmonitor signals for state, change of state, timing and countingapplications using an external contact sensor.

An analog sensor and readout module is generally represented by numeral84. The configuration shown has three analog sensor ports arranged,namely 86, 88, 90. The integrated precision pressure port 86 will haveone or two channels, contain temperature compensation means, conversionmeans for converting the signal to engineering units, contain 4/6 wireresistive excitation, and have the ability to measure absolute ordifferential pressures. An optional remote or internal sensor port 88 isincluded that has one 4/6 wire excitation sensor, the sensor beingtypically a moderately accurate process temperature or pressure sensor.An optional remote or external sensor port 90 may be included with one 6wire excitation sensor being connected. The port 90 may be employed ifthe second internal port is not used.

The senor ports 86, 88, 90 are electrically connected to the AnalogExcitation Conditioning Circuit 91 a which in turn is electricallyconnected to the analog multiplexer 91 b. The signal may be directeddirectly to the microprocessor 73, or as in the preferred embodiment, isdirected to the Precision Analog to Digital Converter 91 c. The AnalogMultiplexer 91 b is commercially available from MAXIM Co. under the nameMAX4052A. The Precision ADC 91 c is commercially available from BURRBROWN Co. under the name ADS1211E. The ADC 91 c is electricallyconnected to the microprocessor 73 as shown in FIG. 3.

A minimum of one sensor of any type is needed for collection of data Asnoted above, a maximum of three channels of analog sensors, two of whichcan be pressure (P) or differential pressure (dP) sensors included withthis system. Thus, the integrated analog sensors via port 86 and 88 arehigh accuracy, 6-wire measurements that allowthe following combinations:P, dP, P+P, P+dP. The external analog sensor via port 88 or port 90 isof moderate accuracy and can be 4-wire, or 4-20 mA type that allows thefollowing combinations: pressure (P), differential pressure (dP),resistive temperature detector (RTD), P+RTD, dP+RTD.

An external contact type of sensor, operatively associated with thedigital input capture 82, detects state, change of state, or timing. Aremote digital sensor 91 connected via the RS-485 port 76 may also beemployed, with this type of sensor being commercially available from awide variety of vendors.

A compact wireless modern 91 d is included. The modern 91 d has a UARTcompatible input and can use CDPD data exchange. The modern 91 d has alow power RF output. In the preferred embodiment, the modern 91 d iscommercially available from Sierra Wireless, Inc. as previously noted.An antenna 91 e is shown to transmit data.

According to the teachings of the present invention, one of the possibleinstrument configurations includes a connection to a hardwired land linetelephone network. Additionally, wireless forms of communications may beused that include circuit switched cellular via a telephone modern; adigital terrestrial cellular means that is packet based; or, a digitalsatellite link means that is also packet based. Another option for thetransfer of the data includes use of the RS-232C port 72 to a hand heldterminal device or laptop computer.

Referring now to FIG. 4, a schematic flow chart of a first systemsarchitecture of the present invention will now be described. A pressurefrom any source throughout the oil and gas facility 150 can becommunicated to the FI 2. In the preferred embodiment, the pressure iscommunicated from an oil and gas well 151 completed to a hydrocarbonreservoir. The pressure may be communicated to the FI 2 from down hole,from the well head, from flow lines, from a separator, from a pipeline,process equipment, etc.

In FIG. 4, the pressure from a well completed to a subterraneanreservoir has been communicated to the sensor 4 of the FI 2. An analogtemperature sensor 8 has also been included. The sensors 4, 8 willcollect pressure and temperature data, for instance, and will thentransmit that data to the operating system 12 for processing aspreviously discussed. The operating system will then transfer this datato the field communications module 20, which will be capable oftransmitting the digital information as shown in FIG. 3 as numeral 152.

The field communications module 20 will transmit the digital data to adatabase engine 154 which is commercially available from Oracle Inc.under the name Oracle 8i. The database engine 154 will have loadedthereon field communication software 155 to communicate with thecommunications module 20. The database engine 154 will consist of a datamanager software 156 that is operatively associated with the database158. In the software context, when it is mentioned that it is“operatively associated with”, the phrase simply means that the twocomponents can electronically exchange data between each other. The database 158 will have a table configuration that will enable the storage ofthe various data that has been received. Also included will be a userinterface module 160 that consist of software that will interface withthe server 162 so that the server 162 and database engine 154 cancommunicate.

The information system's architecture also includes the interface 164loaded on the server 162. This interface 164 may also be located at thethird party's location, or loaded onto multiple user computers 166 a,166 b, 166 c, 166 d. Also loaded onto the third party's computer 166a-166 d will be the browser. Thus, at this third party location, theuser may access the data base 158.

The database engine 154 may be located at the operator's own site. Thisallows for security of the data, and control by the operator.Alternatively, the database engine may be physically placed at a thirdsite separate from the operator's site.

According to the teachings of the present invention, multiple FI unitsmay be placed at multiple locations, with the individual FI unit havingthe field communications module wirelessly transmitting to the data baseengine 154. Thus, the database engine 154 will have numerous sensorinformation stored thereon, from multiple measurement points.Additionally, multiple users can access the database 158 from multiplelocations.

FIG. 13, discussed in more detail below, discloses a preferredembodiment to connect multiple FI 2 units. As indicated in FIG. 13, apreferred embodiment, discussed in more detail below, FI units areconnected to the central location 500, which can include the data baseengine 154, and/or other data bases. The central location 500 can alsocomprise a similar data base field communication software to communicatewith the communications modules 20 of each of the fields units 2.

Referring now to FIG. 5, a schematic flow chart of a second systemsarchitecture of the present invention will now be described. Under thisscenario, the pressure from the well 168 will be communicated to thesensor 4 and in turn to the FI 2, which will in turn communicate to thefield communication module 20 which in turn is transmitted wirelessly152 to the data base engine 154. The database engine 154 will haveloaded thereon field communication software 155, data manager software156. The data base 158 will have a table configuration that will enablethe storage of the various digital data that has been received. Alsoincluded will be a user interface module 160 that consist of softwarethat will interface with the web server 170. A server interface 176 isalso included, with the server interface 176 functioning to communicatebetween the data base engine 154 and a web server 170.

As noted in FIG. 5, there are at least two examples of systemsarrangement with this embodiment. First, the server interface 176 may beconnected to the Internet 178, which in turn allows the clients 166 a,166 b, 166 c, 166 d, etc. to be connected.

Second, with the teachings of the present invention, it is possible thatthe field sensors 4, 6 be directly connected to individual clients, suchas the client 166 d, as denoted by the link 184. This link 184 may be awireless link, as previously discussed, or may be a phone line, or otherconventional means. The operator may wish to have this extra link forsecurity reasons, or to have a back-up system. Regardless of the reason,the architecture allows for this type of arrangement.

FIG. 5 also shows the arrangement for the exception reporting. Thus, thedata manager software 156 would allow for the processing of alarmconditions i.e. wherein pressure and/or temperature data exceeds somepredetermined level. Thus, there is written into the software a routinethat will recognize this exception, and the software will automaticallyreport the exception to the clients 166 a, 166 b, 166 c, and/or 166 d aspredetermined.

FIG. 6 is a schematic diagram of one embodiment of the serverarrangement. Thus, a first computer 167 a can be used that iselectrically connected to a second computer 167 b. The computer 167 acan have the user interface, hypertext markup language (HTML), ExtendedHTML (XML) and the field communication loaded thereon. The computer 167b will have the database manager and data base loaded thereon.

FIG. 7 is a flow chart of the digital signal processing of the presentinvention. Thus, the signal from the smart device 300 is received 302 atthe RS-485 device 76 which in turn is transmitted to the UART 304. TheUART will condition the signal to be accepted by the microprocessor 306.Depending on the mode of operation of the operating system, themicroprocessor 306 may then forward the reading to the UART 74 in thestep 308 which in turn is sent 310 to the RS-232C 72. The RS 232C 72allows for a local dump to the local terminal computer 312 where a usercan access the collected data on site, for instance.

Alternatively, the mode of operation may dictate that the data bechanneled to the UART 314 which in turn will channel the signal to thewireless modern 91, as shown in sequence step 316. The modern willtransmit the signal to a remote computer as seen in step 318. From theremote computer, the data may be disseminated via various means such aspreviously noted with reference to FIGS. 4 and 5.

FIG. 8 is a flow chart of the analog signal processing of the presentinvention. Thus, the signal from the analog sensor devices 86, 88, 90are received at the analog excitation conditioning module and analogmultiplexer 320 where the analog signal is conditioned and forwarded tothe microprocessor in step 322. Depending on the mode of operation ofthe operating system, the microprocessor may then forward the reading tothe UART 74 in the step 324 which in turn is sent 326 to the RS-232C 72.The RS 232C 72 allows for a local dump to the local terminal computer328 where a user can access the collected data on site, for instance.

Alternatively, the mode of the operating system may dictate that thedata be channeled to the UART 330 which in turn will channel the signalto the wireless modern 91, as shown in sequence step 332. The modernwill transmit the signal to a remote computer as seen in step 334. Fromthe remote computer, the data may be disseminated via various means suchas previously noted with reference to FIGS. 4 and 5.

FIG. 9 is a flow chart of the sequence of powering the sensors in orderto take readings as well as the sequence of steps of taking a reading.Thus, the operating system generates a wake up signal 354, at a preprogrammed time interval, which will cause the sensors to be powered up356. The sensors will take a reading, as denoted in block 358. Theoperating system will then cause the sensors to be powered off 360.

Thereafter, the operating system will convert 362 the raw sensor values,stored in the cache memory, to real units utilizing a conversionalgorithm as previously stated. The converted readings will then bedisplayed 364 on the LCD. The converted data is stored into the memory366. The operating system will determine the next broadcast time point,pursuant to a predetermined time interval, and at the broadcast time,the field instrument (via the communications module) will send the datato a local computer and over the modern 368. The operating system willthen calculate the next wake up time 370 and thereafter generate asignal which causes the sensors to power down 372 (referred to assleep). After the expiration of the predetermined time interval, a wakeup signal is generated thus generating the loop back to the step seen inblock 354, with the steps being repeated as shown in FIG. 9.

Referring now to FIG. 10, a schematic illustration of the enclosure 400of the present invention will now be described. In the preferredembodiment, the enclosure 400 includes a generally cylindrical base 402that has an outer cylindrical surface 404 that in turn has extendingtherefrom four projecting openings (only openings 406, 408, 409 areshown in FIG. 7). The openings are generally cylindrical in nature andwill have an outer diameter 410 that extends to the inner diameter 412.The inner diameter 412 will have connection means such as an internalthread means 414 that will sealingly engage with an adapter havingmating thread means. All four openings will have similar internal threadmeans. O-rings may be used to aid in sealing. Other connection meansinclude use of pins as well as welding adapters in place. As seen inFIG. 10, the base contains a top 416 with an opening for placement ofthe LCD 418.

The Liquid Crystal Display (LCD) 418 is also shown, with the LCD beingelectrically connected to the printed circuit board. The LCD iselectrically attached to the digital pressure ii readout as previouslystated. Thus, the operator can view the digital pressure readoututilizing the enclosure 400. The LCD 418 is a custom layout availablefrom Varitronix Ltd.

Therefore, the enclosure 400 is a closed container once the adaptershave been placed within the openings. This enclosure 400 represents anexplosion proof closed container. As will be understood by those ofordinary skill in the art, hydrocarbons can be hazardous and/orcorrosive materials. In accordance with the teachings of the presentinvention, the pressure from the wells will ultimately be communicatedto the sensor within the openings. An important aspect to the inventionis to withhold pressure from the inner chamber 229. Additionally, theinner chamber 420 will house the printed circuit boards for the sensor,memory, operating system, modern, battery, etc. Thus, the enclosure mustalso be capable of withstanding an internal blast. Remember, hydrocarbonfluids and gas are extremely flammable with low flash points.

FIG. 11, which is an operations and data flow chart, will now bedescribed. In particular, FIG. 11 depicts the system software & firmwareof the operations and data flow. The operating system contains asupervisor means 90 which technically contains the hardware circuit 62from FIG. 3. The supervisor means 90 also contains additional firmwarethat includes a calibration map loader means 92 a for precision pressuremaps, RTD (resistive temperature detector) calibrations, and specialpurpose calibrations for custom sensors on the external analog inputchannel (i.e. 4-20 mA conversion). Also included is the real time clockmeans 94 that will be continuously powered. The real time clock 94 has aprogrammable delay to the next microprocessor interrupt for datasampling.

The supervisor 90 further contains the interrupts and scheduler 96 fordata sampling. The firmware installer 98 contains a boot loader that canbe accessed via the local terminal or via the remote communicationchannel. The command interpreter means 102 is included and containsmeans for providing the sensor configuration, power managementconfiguration, RTC configuration, UART configuration, memoryconfiguration, display configuration and allows access to raw sensorvalues, process values and various intermediate calculation results.

The measurement data management module 204 is electrically connected tothe supervisor means 90. The measurement data management module 204includes means 206 for generating process statistics and higher levelcalculations done on process variable calculation results. Themeasurement data management module 204 will also contain means 208 fortrending, and means 210 for time compression. Some level of statisticsand process data can be kept for some period of time including thelifetime of the device. In the preferred embodiment, the oldest datawill get compressed the most, while the most recent data is saved athigher resolution (both time and amplitude). Additionally, means 212 forarchiving the data is provided.

The supervisor will be operatively connected to the system functionsmodule 214. The system functions module 214 includes the powermanagement means 216 that allows for switched modern power, switchedanalog circuit power, and in some cases switched external power. Alsoincluded will be system identification 218 that will digitally containinformation such as serial number, production lot, hardware and firmwarerevision codes, model number, build date and factory, originalconfiguration, current configuration, first day placed in service andother similar data.

Additionally, a device maintenance means 220 that includes maintenancelogs, with the logs containing the last service date, operator andrecord locator number; last calibration date, calibration source,calibration ID and current calibration status; enclosure access logsthat detail when the enclosure has been opened and detect that servicewas performed, and detect if tampering has occurred. The devicemanagement 220 will also update the maintenance history and run-timeoperating statistics.

The device management 220 has preventative maintenance indicators thatinclude count down clocks, etc. to notify of upcoming preventativemaintenance sessions. Additionally, there are checks for batterymaintenance/replacement that may indicate when battery charge is low,the batteries are old, or won't recharge properly.

A watchdog timer means 222 has been included. The systems functionsmodule contains a non-volatile memory control that will have a cachememory and EEPROM memory. A system errors and alarms means 224 isincluded that indicates if the error is recoverable during a currentsession, or recoverable on the master reset, or recoverable only withphysical intervention. Another feature is that the system will havechecks and diagnostics activated on start-up, a system for performingself-checks/diagnostics, and a monitor for the status of the RTC (realtime clock). Means for monitoring internal analog points is included.These checks are triggered on power up, or manually, or through thelocal terminal connection, or remotely through the wireless connection.System warnings and error alarms are produced out of the communicationsports when a diagnostic fails or receives a suspicious value. The systemlogs these error/exceptions, and a local error history record is kept incase of outgoing alarms are missed.

Another module of the operations and data flow is the process monitoringmodule 226. The module 226 includes a sample sequence algorithm 228which determines when and how to 1i shift between various sample rates,trigger modes, calculations and data analysis. Thus, the process datasampling options include scheduled sampling where process values aredetermined at a suitable rate on a fixed or sequenced schedule.Typically, this sampling is used when the process values vary slowly ornot at all. Also available is adaptive sampling wherein process valuesare determined at a dynamic rate determined by the recent history of theprocess. The adaptive sampling is typically used when process valuesvary erratically.

The process monitoring contains process variable calculation means 230that allows for AGA 3 or AGA 8 and API “Standard” gas-fluid calculationsthat provide for material composition correction. The calculation means230 includes various fluid characteristics, tables, and equations andmay contain orifice meter device descriptions (materials, dimensions,specific ID's, etc). Among the process data calculation options are theability to obtain current values and states for the process and system.Additionally, the history of values and states for the process andsystem can be obtained. This history can be used to determine processstatistics such as the maximum, minimum, average, total, etc. of theparameters thus measured.

Also included in this module is the process alarm means 232 that isbased on captured, converted and combined signals from both local and(if installed) remote sensors. The process alarm means 232 may usedefault or predefined process monitoring algorithms and alarm conditionsor user defined algorithms and logic. This module will notify of analarm condition through the display and will send a message out theRS-232 and wireless ports.

The measurement trigger rates means 234 has single, multiple and/orauto-repeating sequences that may be combined in larger sequences usingvarious process dependent algorithms. Means 234 contains adaptive andconditional sampling methods that include process ii variable triggeredsequences and sampling rate changes. The triggers may be derived fromprocess variables, proportional, rate, derivative, integral and stateinputs. The sampling methods include remotely triggered sequences andsampling rates, and allow remote commands to force branches withinsequence logic.

Another module is the data acquisition 236 that includes a sensorresponse conversion 238. For the high precision pressure sensors, aniterative interpolation is used across a pressure-temperature map untilconvergence. For other simple sensors, an appropriate 1-D conversion maybe used to compensate the sensor's transfer function. A ADC readout andcontrol 240 is provided that allows for ADC settings 242 and MUX control244, that is connected to multiple analog sensors, and ADC channelselection 246.

A communications and protocol manager module 248 is also included thatallows the operator to select appropriate data representation andprotocol for communication channels. An RS-485 port 76 is included thatmay be connected to the external smart sensors, or may be connected toother control systems, or may be connected to alarm fuictions, or may beconnected to process monitoring. The RS-232C port 72 is included whichallows for a local terminal access to the command interpreter 102. TheRS-232C allows for local data retrieval, optional periodic qualitycontrol and calibration access, optional firmware update access, sensorconfiguration, hardwired configuration, local diagnostics and debugaccess.

A wireless channel management means 254 is included that contains datacompression means 256, error correction means 258, data encryption 260and means for authorization and access control 262. Data encryption iscommercially available from several vendors and the data encryptionmeans may use the Data Encryption Standard (DES). Data encryption means260 is commercially available from RSA Data Security Inc. under thestandard RC-4 and RC-2, and both of these are covered under the standardCDPD 1.1, which the wireless modern uses.

Compiled data may be extracted through the local terminal port by aservice technician. The data can then be manually carried to datamanagement facility. This data dump mode is used primarily as a back-upif the remote data dump mode is inoperative or unreliable.

FIG. 12 is a schematic diagram illustrating the hardware architecture ofa preferred embodiment of the system. As illustrated in FIG. 12, thesystem comprises the field unit FI 2 connected to the network datareception servers, located at central location 500.

The field unit FI 2 comprises the elements discussed above andillustrated, for instance, in FIG. 1. In particular, the field unit FI 2may comprise sensors 4, 8 as well as a processor 550 and memory 552. Inthis way, the field unit FI 2 can complete the steps described above,including those illustrated in FIG. 9. In particular, the processor 550can power up the sensors 4, 8 take the reading and log or store the datacorresponding to the readings in memory 552. In addition, the processor550 interacts with the application layer protocol 560 to communicate thedata indicative of the reading to the central location 500. Thiscommunication can occur through a wireless network, shown generally byreference numeral 600, a public network, shown generally by referencenumeral 610, or any other type of network or combination of networkswhich can be used to transmit data. In other words, it is understoodthat while the present invention is described with respect to specifictypes of networks for communicating data and/or commands for specifictypes of protocol, the invention is not necessarily limited to any onetype of network topology or any one type of transport protocol.

In order to facilitate the transmission of the data, the applicationlayer protocol 560 generally has two components, namely a component 560a located at the field instrument unit FI 2 and another component 560 blocated at the central location 500. In this way, data transmission canbe accomplished between the data reception servers at the centrallocation 500 and one or more field units FI 2 located at remotelocations with respect to the central location 500.

As illustrated in FIG. 12, the application layer protocol 560 canperform the necessary steps to transmit the data. For instance, theapplication layer protocol 560 can assist in authenticating the data,encryption of the data and compression of any data. In other words, theapplication layer protocol can assist in all transmission controlfeatures. The application layer protocol 560 may reside or form part ofthe other means referred to above, such as the data compression means256, the error corrections means 258, the data encryption 260 and themeans for authorization and access control 262, or, may be a separatesingle unit which performs these functions. The application layerprotocol 560 a,b may also be associated with, or reside in thecommunication units or modules 20, 91 d in the field instrument FI2 andthe central location 500, respectively. The application layer protocol560 a may also reside in the software component of the microcomputer 64.

The application layer protocol 560 b located at the central location 500receives the data, de-encrypts the data if necessary, and authenticatesthe data using standard error detection and correction techniques. Thecentral location 100 then has a transmission gateway 510 comprisingtransmission gateway servers. The transmission gateway servers mayconvert data received from the field units FI 2 to a form which can beused and/or stored at the central location 500. In a further embodiment,some data may pass directly to the central location 500 depending on thetransport protocol and carrier network topology selected by the systemdesigner in view of the communication module 20 installed in the unit FI2. The transmission gateway 510 is connected to the data server 520which accepts incoming data and, assuming the data is successfullyauthenticated and validated, submits the data indicative of the readingsfor insertion into the data base 558. The data base, through the database server or engine, acts as a central repository for the readingsfrom all of the sensors 4, 8 of each of the field instrument sensors FI2. The data base 558 will store the readings from each of the sensors 4,8 identifying the sensor 4, 8 and the corresponding field unit FI 2,which made this the reading. The data base 558 may also store otherinformation such as environmental information including the times thereadings were made.

It is apparent from FIG. 12, that the application layer protocol permitscommunication to and from the data reception service at the centrallocation 500 and each of the field instruments FI 2. In particular, byhaving the application layer protocol 560 a at field unit FI 2 and thecorresponding application layer protocol 560 b at the data receptionservers of the central location 500, data, instructions, and commandscan be transferred between the data reception servers at the centrallocation 500 and the field instrument units FI 2 located remotelytherefrom.

Information can be transmitted between the application layer protocol560 a at the field unit FI 2 and the application layer protocol 560 b atthe data reception servers of the central location 500 by any knownmeans. However, in a preferred embodiment, the application layerprotocol 560 communicates information through the use of messages.Messages may consist of a header and body which may have the followingformat:

Message Header Format: Message Message Type & Error Code Transaction IDMessage Reserved Type Subtype Subtype 1 byte 2 bytes Length 2 bytes 1byte 1 byte Version msbyte=index 2 bytes 1 byte lsbyte=instance

The header may be followed by N bytes of message data. The format ofthis data is dependent on the message type, subtype, and version. Anyunused fields are generally set to zero.

There can be many classes of messages. For example, the messages mayinclude command messages which are sent from an initiator, such as alaptop computer or a server or a computer located at the centrallocation 500, to request data, or an operation, from a target such as afield instrument unit FI 2. Messages may also include response messageswhich are sent back from the target, such as the field instrument FI 2,to the initiator.

There may not be a one to one relationship between the commands and theresponses. For example, some commands may not require a response, butrather may send instruction to the processor 550 at a field instrumentunit FI 2. Furthermore, some commands may trigger multiple responses. Inorder to track the responses, the transaction ID field may be used as acounter which increments for each new command transaction initiated byan initiator. A transaction may consist of one message of severalmessages. The transaction ID is returned by the target of a command backto the initiator in all responses to that command. This is a potentiallysimple means to match responses to commands by parsing the messageheader.

The transaction ID may also consist of two sub-fields, namely a valueand a instance. The value sub-field increments for each new commandtransaction. There is an unsigned value with zero reserve to indicatemessages that are not tied to a transaction, such as broadcast messages.Hence the range of indices for a transaction ID is from 01 to FF inhexadecimal notation. The instance sub-field is used to denote thespecific part of the transaction such as the start of transaction, endof transaction, etc. This may be assigned a value with zero indicatingthe last message of a transaction, positive numbers indicating thenumber of remaining messages in the transaction, negative numbersindicating both the first message of the transaction and the remainingnumber of messages in the transaction. Accordingly, for commands whichelicit multiple responses, the transaction ID for each response will beidentical.

With respect to other fields which may exist in the message header, itis apparent that the message type field defines a major class of themessage such as command or response. The message header may alsoidentify the target and/or initiator to facilitate in transferringinformation. The error code field is generally used for responses onlyand to assist in error detection and correction. The message lengthfield indicates the length of the entire message including the header.The last two fields may be reserved for future use. One advantage ofusing this message format is that information can be transferred betweenthe field instrument unit FI 2 and other components in the network, suchas the network data reception servers at the central location 500 or alaptop, server or other computing device located in another location,even if the internal functions and data representations are notcompatible with each other. In other words, a further function of theapplication layer protocol would be to act as a universal translator toenable all the components in the network to communicate with each other.

As stated above, the field unit FI 2 can be polled for the data when thedata reception servers at the central location 500 desire the data. Thepolling may occur after the field instrument unit FI 2 begins aconnection to the central location, or, in a preferred embodiment, couldbe instigated by the central location. In this way, command signals canbe sent from the central location 500 to a specific field unit FI 2 inorder to cause the field unit FI 2 to perform a measurement and transmitthe data back to the central location. In addition, the data receptionservers at the central location 500 can send command signals to aspecific field instrument unit FI 2 to cause the processor 550 to storecommand signals indicating the time and type of reading which should bemade. The processor 550 can make the reading at the specific time andtransmit the data back to the data reception servers at the centrallocation 500, when the readings are made, or alternately, store the dataat the memory 552 located remotely at the field instrument unit FI 2.The processor 550 may process the raw data received from the sensors 4,8and transmit the processed information to lower data transmissionvolume, as discussed in more detail below.

In a further preferred embodiment, the remotely located field instrumentFI 2 can determine the status of the network, such as the wirelessnetwork 600 and the public network 610, as well as determine the statusof the data reception servers at the central location 500. If any one ofthese components is not operating optimally or is congested, theprocessor 550 at the field instrument FI 2 can store the readings at thememory 552 and then automatically try to retransmit the data at a latertime.

In a further preferred embodiment, the field instrument FI 2 areautonomous, meaning that they can automatically initiate a connection tothe data reception servers at the central location 500. For example,once a the field instrument unit FI 2 is initially activated, they canautonomously and automatically notify the data reception service at thecentral location, of this fact. Likewise, if a particular fieldinstrument unit FI 2 is temporarily disconnected from the data receptionservers at the central location 500, for whatever reason, including atemporary failure of a component of the field instrument unit FI 2 or ofthe network, such as the wireless network 600 or public network 610, thefield instrument unit FI 2 can send a signal advising the data receptionservers at the central location 500 that it is now operational.Furthermore, the field instrument unit FI 2 can at that time transmitany data representing readings made during the down time, and, indicatethe time the readings were taken.

For example, once the field instrument unit FI 2 is initially activated,or, if it is activated after a temporary interruption or a catastrophicfavour, the field instrument unit FI 2 may either receive a signal fromthe central location 500, or, send a signal to the central location 500indicating its presence. In either case, the initial signals willtransmit information to set up or initialize the field instrument unitFI 2 into the network. This information may include informationidentifying the field instrument unit FI 2, and, setting the date andtime of the field instrument unit FI 2, or, confirming that it is thesame as the date and time of the network data reception servers at thecentral location 500.

Accordingly, it is apparent that the system disclosed in FIG. 12 has ahigh degree of robustness in that it can survive a failure of any one ofthe components in the system, including the network, such as thewireless network 600 and/or public network 610, as well as a temporaryfailure in either the data reception servers at the central location 500or a component of the field instrument unit FI 2. In particular, if theprocessor 550 at a field instrument unit FI 2 has been pre-programmed totake readings at specific times, it will continue to do so even if thereis a failure in other components of the system and the data representingthe readings cannot be transmitted to the data reception service at thecentral location 500. Rather, the processor 550 will store the time,date and readings locally at the memory 552 until such time as thenetwork can transmit the data and the data reception servers at thecentral location 500 can receive the data. The field instrument unit FI2 can also reassert autonomously and automatically their existence,either initially when they are first connected to the data receptionserver at the central location 500, or, offer a temporary interruptionor catastrophic failure.

Clearly, this provides an advantage particularly in the embodiment wherethis system is being used near hydrocarbon fluid and gases which areextremely flammable with a low flash point. For example, should acatastrophic explosion occur, and the field instrument unit FI 2 is notdirectly affected by the explosion, it can continue to take readings andstore them locally at the corresponding memory 552. This data, when thefield unit FI 2 is later reconnected either to the previous data serversat the central location 500, or if this central location 500 has beenirreplaceably destroyed, to a new central location 500 and new datareception servers, the field instrument unit FI 2 can transmit datarepresenting the readings made during the down time of the system tore-populate the database 558. These readings could be instrumental indetermining the cause of any catastrophic event and/or assisting adesign change in the future to avoid such catastrophic events.

FIG. 13 illustrates schematically the system architecture for apreferred embodiment employing a star network, shown generally byreference numeral 700, for monitoring and data collection from a numberof remotely located field instruments 2. The field instruments 2 areconfigured to transmit data, and may be of an identical constructionsuch as that described as the pressure instrument FI2 with reference toFIG. 1. More preferably, however, the instruments 2 are adapted to senseand provide data respecting a variety of differing operating conditionsover a given geographical region or oil and gas installation.

As discussed above, if the central location 500, and/or one or more ofthe field units FI 2 are damaged in a catastrophic event, the remainingfield instrument units FI 2 will continue to take measurements and storethem in the local memory 552, pursuant to their previously receivedinstructions. Therefore, the system illustrated in FIG. 13 will continueto operate, and in particular the field instrument unit FI 2 will takereadings and store them locally at memory 552, for later transmission tothe central location 500 should the network be congested, or a failurehas occurred either temporarily of the network or the data receptionservice at the central location 500, or, a larger catastrophic event.

In addition, as stated also with respect to FIG. 12, the star network700 can transmit over a wireless network 600 and/or a public network610, or any other type of network for communicating data and/orcommands. Accordingly, it is understood that while the present inventionis described with respect to specific types of networks forcommunicating data and/or commands, it is not necessarily limited to anyparticular of network, or, any one type of protocol. Furthermore, it isunderstood that the networks, described herein, and in particular thestar network 700, can be mapped out across one or more various subnetworks, such as the Internet, the Public Switch TelecommunicationNetwork (PSTN), Cellular Digital Pocket Data (CDPD) and Satellitenetworks including Iridium networks.

Accordingly, the present invention is independent of the networks uponwhich it is operating. In other words, one or more various sub-networks,such as the Internet, the PSTN, CDPD and Satellite networks can be used.Furthermore, the invention can accommodate ongoing sub-network changeswhich will inevitably occur as these various sub-networks, and newsub-networks, continue to improve and change.

To map across multiple networks or sub-networks with differenttopologies instructions, unique application layers and section layersmay be added in the communication system to ensure the connection fromeach of the field instrument units 2 to the central location 500. It isalso understood that different field instrument units 2 may usedifferent sub-networks, or combinations of sub-networks, to communicateto the same central location 500. Accordingly, the network of thepresent invention, such as the star network 700 as illustrated in FIG.13, can map itself over the networks shown below: CDPD Iridium SatelliteInternet Network Topology Star Star Bus Network Structure Client/ServerClient/Server Peer to Peer

As indicated above, different network structures may be used in order tocommunicate information in the network 700. In a preferred embodiment,where the network topologies is a star network 700 as illustrated inFIG. 13, the network structure is a client/server structure. In such astructure, the client is generally understood to initiate the connectionbetween the client in the other element in the network, generallyreferred to as the server. In this structure, the client will decipherthe input it receives and determine the process that will be executed byeither the client or the server. If the required process is tocommunicate with the server, then the client will do so. If the requiredprocess is to be performed by the server, the client sends the requestto the server. Likewise, the definition of a server is generally theentity and the network 700 which authenticates a client requesting aresponse and service from the server. The server often stores data forthe process and sends data to the client when required. The server mayalso store a program module for the client and serve up the program tothe client on demand. One advantage of the network shown in network 700is that either the network data reception servers of the centrallocation 500 or any one of the field instrument units FI 2 can act asthe client or server. Having interchangeability of the client and serverfunctions in the star network 700 increases the versatility of thesystem. In particular, depending on the task to be achieved, thefunctions promptly change to achieve the desired task. This alsoincreases the robustness of the network 700 by permitting the fieldinstrument unit FI 2 to act as client after a temporary malfunction orcatastrophic failure.

In addition, the star network 700 can survive, by design, in spite ofthe total failure of the central location 500. The field instrumentunits FI2 are equipped with the alternate central location in its memoryso that FI2 will automatically switch the address vector. When the fieldinstruments FI2 finds the active alternate central location 500, FI2will automatically repopulate the alternate central location 500 byfilling the missing data.

Furthermore, an added advantage of the interchangeability of the clientand server function between the field instrument unit FI 2 and thenetwork data reception server at the central location 500 is the abilityto parrell process data throughout the network 700. In other words, asdescribed above, the processor 550 at each field instrument unit FI 2can be instructed to execute programs independent of the other elementsin the network 700, including the network data reception servers at thecentral location 700. Consequently, each processor 550 at each remotelocation can execute programs simultaneously. This allows for alarge-scale parrell processing at the network level for the purpose ofdata delivery. This is facilitated by the interchangeability of theclient and server functions between the field instrument unit FI 2 andthe data reception servers at the central location 500. For example, ifthe processor 550 at the remote locations are instructed to process theraw data and transmit processed information, this can greatly decreasethe processing requirements placed on the network data reception serversat the central location 500, and, can lower the data volume transmissionacross the entire network 700. This is an advantage over a master-slavebase communication protocols, such as the supervisory control and dataacquisition and (SCADA) systems which do not provide for autonomousoperation of field instrument units FI 2.

It is further understood, as also discussed above, that while thesupervisory control and data acquisition (SCADA) systems use amaster-slave base communication protocol the present invention does notnecessarily require such a relationship, and, such a relationship isexplicitly removed if a network, such as the Internet, is utilized withthe TCP/IP protocol. Likewise, while the star network 700 topologytypically uses a client/server relationship where the client initiatesthe connection between the client and server and a server authenticatesa client requesting a response or service from the server, the starnetwork 700 is not necessarily restricted to such an arrangement.Rather, the star network 700 could have interchangeable client andserver function. In other words, as discussed above, data and commandscan be interchangeably sent from the field instrument units FI 2 to thecentral location 500, in spite of the star network 700. In other words,and depending upon the task to be achieved, the field instrument unitsFI 2 and the network data reception servers at the central location 500may change functions to achieve the desired task.

FIG. 14 illustrates the general overview of the architecture of theserver/data base system, shown generally by reference numerals 702 inFIG. 14, parts of which have been described above. In particular, FIG.14 illustrates the flow of data amongst the different layers of theserver/data base system 702, namely the Data Collection Layer 710, theData Prioritization Layer 712, the Data Processing Layer 714 and theDatabase 558. Furthermore, the server/data base system 702 can beconsidered to have three separate tiers. The first tier comprising theData Collection Layer 710 and the Data Prioritization Layer 712,involved in collecting and prioritizing the data. The second tiercomprising the Data Processing Layer 714 which processes the collecteddata. The third tier can be considered the Database 558 itself. Thecomponents of the server/data base system 702 will now be discussed.

In addition to the Data Collection Layer 710, the Data PrioritizationLayer 712, and the Data Processing Layer 714, the server/data basesystem 702 also comprises the field instrument FI 2 which collects thedigital reading output data from the various remote locations, whichremote locations may be geographically separated. The system 702 alsocomprises Incoming Message Queues 720 which is used to store validbinary data from the field instrument unit FI 2. The Incoming DataMessage Queues 720 also include a Data Request Message Queues (notshown) for requesting updated data for authentication.

The system 702 also comprise Outgoing Message Queues 722 which arequeues used to store binary data that need to be sent back to the fieldinstrument unit FI 2 on the next connection thereto. This data couldinclude items such as Yesterday's Volume, etc., which may be required bythe field instrument unit FI 2 in order to perform further measurementsand/or provide processed digital output readings, as opposed to digitaloutput readings which may merely comprise raw data. The Outgoing MessageQueues 722 also contain data for the Data Collection Layer 710 and alsoinclude the registration confirmation number.

The system 702 also comprises other queues as follows:

The Alarm Message Queues 724 contain all alarm data generated by all ofthe layers 710, 712 and 714. This alarm data may include invalidconnection notifications, bad connection channel notifications, invaliddata notifications, missing data point notifications and no trendnotifications. The Prioritized Data Message Queues 726 contains storedbinary data, similar to the data which may be stored in the IncomingMessage Queues 720 except that they are re-ordered with more importantdata stored at the front of the queues. For example, the PrioritizedData Message Queues 726 may have cry-out alarm data from the fieldinstrument unit FI 2 put in front of the data and the queue so that itcan be processed as early as possible. The prioritized data from thePrioritized Data Message Queues 726 are then sent to the Data ProcessingLayer 714 for processing.

The files, shown generally by reference numeral 730, 731, in the system702 include various log files from the different layers 710, 712 and714, as well as temporary data files, and other files which may be usedby the system 702 as discussed below. The files 730, 731 are used toprovide more information about the system 702 when problems occur, and,to provide temporary storage for data before the data is saved to theDatabase 558.

In a preferred embodiment, the Database 558 is used to store allrelevant data generated by all of the layers 710, 712, and 714. The dataincludes Alarm data, Sensor data, Wellhead data, Flow data and QuantityTransaction Records (QTR's). The data base manager program is preferablyprovided by Oracle (trade name).

The operation of the various layers will now be discussed. The DataCollection Layer 710 is principally responsible for acceptingconnections from the field instrument unit FI 2. Once the connection isaccepted, the binary data from the tool connected to the correspondingfield instrument unit FI 2 will be authenticated to ensure integrity ofthe data. If the data is valid, the Data Collection Layer 710 stores thedata in the Incoming Data Message Queues 720. At the same time, the DataCollection Layer 710 will check the Outgoing Data Message Queues 722 andsee if there is any data needed to be sent back for this connection tothe field instrument unit FI 2, and if so, the data will be retrievedfrom the Outgoing Data Message Queues 722 and sent to the toolassociated with that particular field instrument unit FI 2. The DataCollection Layer 710 may also use the data from the Outgoing DataMessage Queues 722 to authenticate the connection.

If the Data Collection Layer 710 detects any error while receiving datafrom the tool connected to the corresponding field instrument unit FI 2,the Data Collection Layer 710 will report the error into Log Files 730.The type of error which may be detected includes invalid connection andbad channel detection. In some cases, this Data Collection Layer 710will generate an alarm, through any possible means including emailnotification, and will also send the alarm data into the Alarm MessageQueues 724 so that the alartn information can be saved in the Database558.

With respect to the Data Prioritization Layer 712, the main purpose ofthis Layer 712 is to make sure that important data will be processed bythe system 702 as soon as possible. The Data Prioritization Layer 712receives binary data from the Incoming Data Message Queues 720 anddetermines what types of data it is. Once the type of data isdetermined, a priority is assigned and a binary message is passed ontothe Prioritized Data Message Queues 726. Any binary data with higherpriority will be put to the head of the Prioritized Data Message Queues726 so that it will be processed first by the Data Processing Layer 714.If an error occurs in a Data Prioritization Layer 712, it will reportthe error to Log File 731.

The Data Processing Layer 714 is the main processing centre for data ofthe system 702. The Data Processing Layer 714 consists of the DataProcessor Module 740, the Database Updater Module 742 and variousUtility Modules 744. The Data Processor Module 740 and Database UpdaterModule 742 may optionally be combined into one single executable.

The Data Processor Module 740 receives binary data from the PrioritizedData Message Queues, parses the data according to the Application LayerProtocol 560 discussed above and generates an IMV value, QTR's and Flowdata based on the parsed data. That data, as well as the parsed data,will be saved to buffers in memory. The same data will also be saved totemporary data files in case the system 702 crashes. The IMV values willbe sent to the Outgoing Data Message Queues 722 so that the DataCollection Layer 710 can send the values back to the tool of thecorresponding field instrument unit FI 2 on the next connection to thefield instrument unit FI 2. If required, the Data Processor Module 740may retrieve data directly from the Database 558 in order to process thedata properly. If the Data Processor Module 740 encounters an errorwhile processing data, the error will be reported to the Log Files 731.The type of error this module will detect includes invalid data with avalid type, missing data points, no data package (namely no trendrecords) and other types of errors. In some cases, an alarm will begenerated and the alarm data will be saved to the alarm buffers in theProgram and Temporary and Data File 731. The data processed by the DataProcessor Module 740 may include Trend Data, Wellhead Data, IMv values,Flow data and QTR's. The Data Processing Module 740 may process the dataaccording to known algorithms such as AGA-3-92 (Orifice Metering ofNatural Gas and other related hydrocarbons), AGA-8-94 (CompressibilityFactors of Natural Gas and Other Related Hydrocarbon Gases) and Basesoftware modules such as the “Gas Orifice Flow Program C LanguageComputer code Using A.G.A. Report No. 3 (1992) and No. 8 (1994), GOFLIBCSource-A Version 1.3” as well as any other algorithms presently known orwhich may be developed in the future.

The Database Updater Module 742 is principally responsible for savingprocessed data into the Database 558. The Database Updater Module 742will receive data from Alarm Message Queues 724 and stored in theDatabase 558. The Alarm Message Queues 724 may not necessarily have datato be saved to the Database 558 all the time. So the Database UpdaterModule 742 will regularly wake up and check for data from the AlarmMessage Queues 724 and then save the data to the buffer in memory if anydata exists. The Database Updater Module 742 also check the buffers tosee if there is data to be saved, but generally will wait untilsufficient data is accumulated in the buffers before it is saved to theDatabase 558. In this way, the Database 558 is not overwhelmed withconstant access from the Database Updater Module 742, and, the Module742 can make reasonably certain that the data will be saved in theDatabase 558 in a timely fashion. If the Database Updater Module 742encounters errors while processing the data, the errors will be reportedto the Log File 731.

The Utility Module 744 is used in cases where data needs to becalculated once per day, or, in a predefined schedule. One example couldbe the calculation of Yesterday's Volume YVOL. In order to perform thesetasks in an efficient way, the Utility Modules 744 deal with one or moreof these tasks. For example, the Yesterday's Volume Utility Module YVOL744 is responsible for waking up at a pre-defined time during the day,and, retrieving data from the Database 558 and calculating the volumefor each tool associated with each field instrument unit FI 2. Thecalculated data is then saved to the Outgoing Data Message Queues 722.If the module YVOL 744 encounters an error while processing the data,the error will be reported to the Log File 731.

The Quantity Transaction Records recalculation Utility Module QTR Recalc744, from time to time, recalculates the data, such as the flowparameter changes, to ensure that the data is correct. The ZID UtilityModules ZID 744 calculate the data updates which may be required by theData Collection Layer 710 to authenticate any data coming from time totime, the ZID data may be updated in the Database 558 but may not beupdated in the Data Collection Layer 710. The Data Collection Layer 710will detect and outdated ZID data and send a request to a ZID RequestMessage Queue (not shown) for the new and updated ZID data. The ZID DataUpdate Module will regularly check this queue for any request from theData Collection Layer 710. If a request is found, the ZID Utility ModuleZID 744 will retrieve the data from the Database 558 and send it to theOutgoing Data Message Queues 722 so that the Data Collection Layer 710can forward it to the appropriate field instrument unit FI 2. If the ZIDUtility Module encounters any errors while processing the data, theerrors will be reported in the Log File 731.

The Utility Module 744 may have additional modules to perform additionaltasks. For instance, the Module 744 may have a registration confirmationnumber which confirms registration numbers to the Data Collection Layer710 to ensure that the correct encrypted information is being providedby a field instrument unit FI 2. This can occur, for instance, when afield instrument unit FI 2 automatically and autonomously connects tothe central location 500, as described above. This could also occurafter a field instrument unit reconnects to the system from a temporaryprolonged interruption. More preferably this confirmation may occur atthe beginning of each connection to a field instrument unit FI 2.TheUtility Module 744 can provide a confirmation number to the DataCollection Layer 710 to confirm the encrypted identification numberbeing received from the field instrument unit FI 2 in order to improvethe security of communications from the field instrument unit FI 2 tothe Database 558. Additional security features include the layers 710,712, 714 authenticating the information being received, and, having theDatabase 558 located behind a firewall. Furthermore, when a new fieldinstrument unit FI 2 is to be added to the system 702, the encryptedidentification number unique to the new field instrument unit FI 2 canbe previously stored in the system 702. This way, if the fieldinstrument unit FI 2 automatically and autonomously connects to thesystem 702, the system 702 will have the information required toauthenticate the new field instrument unit FI 2.

As noted earlier, in one of the preferred embodiments, the collecteddata is communicated through the wireless modern to a remote point. Thiscommunication may be initiated either by the instrument via theinstalled operating system or initiated by a remote user-databaseserver. The data may be routed through a public telephone network, orthe Internet or a private communications network to one or more users ordatabases utilizing TCP/IP. In yet another mode, data is exchangedduring an interactive session to provide “real time” readout to eitherthe local terminal or a remote user.

In the alarm mode, process and system status information is sentautomatically through one or more of the instrument's communicationchannels. Data delivery is initiated when a process value calculation orsystem error determines that an alarm condition exists. Typical exampleswould be low flow, over pressure, total volume, limits etc.

APPLICATIONS

An application of the novel instrument and system herein disclosedincludes flow metering. The instrument samples data at a rate of up toonce per second to enable high temporal resolution flow calculations tobe performed. The system would be suitable for custody transferaccounting, point-of-use metering, and transmission pipeline leakchecking. The instrument normally acts in a remote data dump mode todeliver logged flow data and flow statistics to a user's database via awireless digital modern. If required, the instrument can switch intoalarm mode to signal that a process variable or state is out ofspecification or it can be periodically interrogated to read processconditions. The location of the instrument would include the wellhead orpipeline monitoring station. Communication means include wirelesscommunication provided either by terrestrial cellular service (digitalpacket or circuit switched) or digital satellite link. The primaryrequirements would be for remote, unattended and accurate collection andtime stamping of flow rate and total volume data.

Another application would be flow metering using orifice meters. Theinstrument would require an internal analog P sensor, an internal orexternal dP sensor (as required by the accuracy needs of the location)and an external RTD temperature sensor. Flow rate or total volumethrough an orifice meter determined using orifice characteristics andAGA flow equations.

Yet another application would be with a turbine or displacement flowmeters. The instrument requires an internal analog P, an external RTDtemperature sensor and one or more digital input capture channels tocount pulses from the flow meter. Accurate flow rate determination isachieved by using pressure and temperature compensation in conjunctionwith the digital input count rate.

Still yet another application includes an ultrasonic and multi phaseflow meters. The instrument requires an internal analog P, an externalRTD temperature sensor and a digital communication port (RS-485) tointerface the ultrasonic flow meter. Accurate flow rate determination isachieved by using the pressure and temperature values to determine theReynolds number of the flow profile past the flow meter, which in turnallows accurate correction of the flow meter readings.

With the teachings of the present invention, the instrument and methodcan be used for production monitoring and optimization. The instrumentsamples data about once per minute to monitor production pressure.Instrument acts in a remote data dump mode to deliver logged pressuredata and statistics to a user's database. If required, the instrumentcan automatically switch into alarm mode to signal that a pressure isout of specification or it can be periodically interrogated to read thecurrent pressure. The instrument would be located on or near thewellhead. Communication means includes wireless communication providedeither by terrestrial cellular service (digital packet or circuitswitched) or digital satellite link. Primary requirements includeremote, unattended determination of wellhead pressure. Wellheads wouldbe equipped with an instrument using both a P and RTD sensors. Pressuremeasurement rate is on the order of minutes to hours, typically timestamped, logged and dumped after many days. Instrument generates analarm immediately if pressure deviates outside an establishedperformance band.

Although the preferred embodiment describes the system as includingpressure sensors 4,6, the invention is not so limited. It is to beappreciated that the system may also be used in the monitoring andmeasuring of other characteristics and/or readings of different types offacilities, oil and/or gas or other facilities, and other sensors maytherefore be used either with or without the enclosure. Thesecharacteristics can include pressure, differential pressure, volume,energy, mass, distance, viscosity, specific gravity, frequency,electrical current and voltage, and molar heating volume.

While preferred embodiments of the present invention have beendescribed, it is to be understood that the embodiments described areillustrative only and that the scope of the invention is to be definedsolely by the appended claims when accorded a full range of equivalence,many variations and modifications naturally occurring to those skilledin the art from a review thereof.

1. A method of measuring a reading at a remote location on a hydrocarbonprocess line, the method comprising: at said remote location collectinga first analog reading with a first sensor; converting the first analogreading to a first digital reading; collecting the first digital readingfrom said first sensor in a control means for receiving, processing, andstoring the digital readings, wherein said control means is located atsaid remote location; storing the digital readings at the remotelocation until the digital readings can be transfered to a moderncommunications means for communicating digital data, wherein said moderncommunications means is located at said remote location; converting thedigital readings to a digital packet data in the modern communicationsmeans; transmitting the digital packet data with the moderncommunications means; at a central location remote from the remotelocation receiving the digital packet data at a database engine locatedat the central location; providing a web server interface in thedatabase engine; linking the database engine to the Internet; providinga user computer, said user computer having a web browser; communicatingto the Internet; accessing the database engine; monitoring themeasurements from a user computer.
 2. The method of claim 1 furthercomprising: sending a signal from the user computer to the databaseengine, and wherein the signal corresponds to a command to poll saidpressure sensor; transmitting the signal from the database engine at thecentral location to the modern communication means at the remotelocation; receiving the signal in the modern communication means.
 3. Themethod of claim 1 wherein said measured reading is pressure, said firstsensor is an analog pressure sensor and said first analog reading is afirst analog pressure reading.
 4. The method of claim 3 furthercomprising: collecting an analog temperature reading with an externalanalog temperature sensor; converting the analog temperature reading toa digital temperature reading; transmitting the digital temperaturereading to said control means.
 5. The method of claim 4 furthercomprising: locally accessing the storage means from a local terminal atthe remote location; downloading the digital readings into the localterminal.
 6. A system for transmitting a pressure reading obtained froma remote oil and gas facility, said oil and gas facility having apressure, the system comprising: at least one field instrument locatedat said remote oil and gas facility including a digital sensor means,for producing a representative first digital output reading; an analogpressure sensor means, for producing a representative analog pressureoutput reading; means, electrically connected to said analog pressuresensor means, for converting the analog pressure output reading into asecond digital output reading; means, for receiving and storing saidfirst and second digital output readings; means, electrically connectedto said receiving and storing means, for locally accessing said firstand second digital output readings; means, for transmitting said firstand second digital output readings; database means located at a centrallocation distant from the remote oil and gas facility, operativelyassociated with said transmitting means, for storing said first andsecond digital output readings in a plurality of data tables, saiddatabase means including a data manager means for receiving, retrievingand communicating said digital pressure output readings.
 7. The systemof claim 6 wherein said means for transmitting said first and seconddigital output readings further comprises means for authenticating,encrypting and compressing transmission of data from the remote locationto the central location.
 8. The system of claim 7 wherein: said meansfor transmitting said first and second digital output readings comprisesa first part at the central location and a second part at the remote oiland gas facility; the means for transmitting said first and seconddigital output readings authenticate, encrypt and compress/de-compressmessages comprising data, including said plurality of data, commands andresponding to and from the remote facility and the central location. 9.The system of claim 8 further comprising: user interface means,operatively associated with said database means, for allowing access tosaid plurality of data tables.
 10. The system of claim 9 furthercomprising a user computer having means for accessing said userinterface means.
 11. The system of claim 9 further comprises an analogtemperature sensor producing an analog temperature signal; an adapterconnected to said temperature sensor, said adapter being received withinsaid second opening; and means, electrically connected to saidtemperature sensor, for converting said analog temperature signal to athird digital signal.
 12. The system of claim 11 wherein saidtransmitting means comprising a communications module means fortransmitting said digital output readings over networks selected fromthe group consisting of the Internet, wireless, public network, privatenetwork, PSTN and satellite.
 13. The system of claim 12 furthercomprising: a user computer, and wherein said user computer has loadedthereon a web browser capable of reading said plurality of data tablesand a communications link from said user computer to the Internet; and,encrypting means, operatively associated with said transmitting means,for encrypting said digital output readings being transmitted to saiduser computer.
 14. The system of claim 13 further comprising: alarmmeans, operatively connected to the receiving and storing means, forgenerating an alarm condition when an acquired first, second and thirddigital readings exceeds a predetermined minimum or maximum digitalreading limit and communicating the alarm condition to a local computerand/or external server independent of a polling request from theexternal server.
 15. A process for collecting, transmitting andmonitoring sensed characteristics from a remotely locating facility, theprocess comprising: at said remotely located facility, sensing a sensedreading indicative of a characteristic of said facility by way of ananalog sensor; converting the analog sensor reading to a first digitalreading; collecting the first digital reading; collecting a seconddigital reading with an external digital sensor; transmitting the seconddigital reading to said control means; transferring the digital readingsto a control means for receiving, processing, and storing the digitalreadings in a storage means; transferring the digital readings in saidstorage means to a modern communications means for communicating digitaldata, wherein said modern communications means is located at saidremotely located facility; converting the digital readings to a digitalpacket data in the modern communications means; transmitting the digitalpacket data with the modern communications means; receiving the digitalpacket data at a data base engine at a central location remote from theremote location located at the central location.
 16. The process asdefined in claim 15 further comprising: at said located facilityperiodically attempting to transmit the reading through a network to thedata base engine at the central location; and storing the digitalreadings at the storage means located at the remote location until thereadings can be transmitted to the data base engine at the centrallocation over the network and received by the data base engine at thecentral location.
 17. The process of claim 16 wherein said data baseengine contains a data manager and the method further comprises: storingthe digital readings in a table format.
 18. The process of claim 17wherein said database engine further contains a central server interfaceand the process further comprises: providing a central servercommunicated with said database engine via the central server interface;accessing the central server from a user computer; requesting thedigital readings from the user computer; transmitting the digitalreadings to the central server; transmitting the digital readings to theuser computer.
 19. The process of claim 18 further comprising: measuringsaid digital readings; setting a predetermined digital reading minimumlimit and maximum limit; exceeding said predetermined digital readingminimum or maximum limit; recording the exceeding of said predetermineddigital data reading limit; producing an exception signal in response tosaid recording; sending said exception signal to the database.
 20. Theprocess of claim 19 further comprising: transmitting said exceptionsignal to the central server; transmitting said exception to the usercomputer.
 21. The process of claim 20 firther comprising: sending saiddigital readings to a web server; sending said digital readings data tothe Internet; accessing the Internet with a web browser from a usercomputer.
 22. The process of claim 21 further comprising: correctingsaid digital readings for temperature effect corruption by mapping thedigital readings to a temperature value in an iterative fashion; and,back calculating to an adjusted pressure and an adjusted temperature.23. The process of claim 15 wherein the control means has electricallyconnected thereto serial communication means for transmitting theprocessed digital readings, and the process further comprising:providing a user computer having a direct link to said serialcommunication means; connecting to the control means from the usercomputer with the direct link; transmitting the digital reading to theuser computer.
 24. A process for sensing a characteristic at a remotelocation and transferring data indicative of the sensed characteristicto a data base located at a central location, remote from the remotelocation, said process comprising: at the remote location: sensing thecharacteristic at the remote location; producing a digital outputreading indicative of the sensed characteristic; storing the digitaloutput reading in memory located at the remote location; at the centrallocation: storing at a data base data received from the remote location;wherein the digital output readings are stored in the memory until thedigital output readings can be transmitted to and received by acommunication unit at the central location; and wherein a processor atthe remote location determines whether or not data can be transmitted toand received by the communication unit at the central location, and,causes the data to be sent to the communication unit at the centrallocation when the processor determines that the communication unit atthe central location can receive the data.
 25. The process as defined inclaim 24 wherein an application protocol performs at least one of thefunctions of encryption, compression and decompression, andauthentication of messages sent and received between the remote locationand the central location.
 26. The process as defined in claim 24 whereinthe remote location is located at an oil and gas facility, and thecharacteristic being sensed includes pressure and temperature at the oiland gas facility.
 27. The process as defined in claim 26 wherein beforethe processor at the remote location causes the data to be sent to thecommunication unit at the central location the processor processes thedigital output signals indicative of pressure to correct for temperatureerrors based on the digital output signals indicative of temperature,and, causes the processed digital output signals to be transmitted tothe communication unit at the central location.
 28. The process asdefined in claim 24 wherein before wherein before the processor at theremote location causes the data to be sent to the communication unit atthe central location the processor processes the digital output signalsindicative of the characteristic and causes the processed digital outputsignals to be transmitted.
 29. The process as defined in claim 24wherein: upon initial connection of the processor at the remote locationto the communication unit at the central location, the processor sendsand receives information to the communication unit to facilitateoperation of the system.30. A device for communicating pressureinformation from a well facility at a remote location to a data baseengine at a central location, the device comprising: a pressure lineconnected to said facility, said pressure line communicating a pressurefrom the facility.
 30. A device for communicating press information froma facility to a database engine, the device comprising: an internalanalog pressure sensor means, connected to said pressure line, forsensing the pressure and generating an analog reading that is convertedto a first digital pressure output reading in response to the pressure.an external digital pressure sensor means, for producing a seconddigital pressure output reading; control means, for receiving, storingand retrieving said digital pressure output readings; first serialcommunication means for communicating said second digital pressureoutput reading to said control means; a liquid crystal display readoutmeans, operatively communicated with said control means, for displayingsaid digital pressure output readings; means, operatively connected tosaid control means, for transmitting said digital pressure outputreadings stored in said control means to a data base engine located atthe central location, and wherein said transmitting means includes anantenna member connected to a second adaptor means for sealinglyreceiving said antenna member within a third opening in said enclosure;power means, positioned within said chamber, for supplying a powersource to said pressure sensor means, said digital means, said LCDreadout, said control means, and said transmitting means; second serialcommunication means, electrically connected to said control means, forcommunicating said digital pressure output readings to a local terminal;storage means for storing said reading at the remote location; whereinthe control means monitors the means for transmitting the readings suchthat, if the readings can not be transmitted to the data base enginelocated at the central location, the control means stores the readingsat the storage means until the readings can be transmitted.
 31. Thedevice of claim 30 wherein said database engine comprises: a databasemeans, operatively associated with said database engine, for storingsaid digital pressure output reading in a table format; a data managermeans for retrieving said digital pressure output reading andcommunication interface means for communicating said digital pressureoutput reading, and wherein the device further comprises: user computerfor accessing said digital pressure output reading from said datamanager means.
 32. The device of claim 31 further comprising: anexternal analog temperature sensor, said temperature sensor producing ananalog signal; converter means, operatively connected to saidtemperature sensor, for converting said analog signal to a digitaltemperature signal reading; and wherein said control means furtherreceives, stores and retrieves said digital temperature signal reading.33. The device of claim 32 further comprising: processing means,operatively associated with said control means, for correctingtemperature errors in the digital pressure output readings due totemperature dependency at the remote location and transmitting thecorrected pressure output readings to the data base engine at thecentral location.
 34. The device of claim 32 further comprising: processexceptions means, operatively associated with said control means, forsending an alarm at a predetermined digital pressure reading andcommunicating an exception to the user computer.
 35. The device of claim33 further comprising: data encryption means, operatively associatedwith the transmitting means, for encrypting the output data to the usercomputer.
 36. The device of claim 31 wherein said transmitting meanscomprises: a modern connectable to a hardwired land line telephonenetwork.
 37. The device of claim 31 wherein said transmitting means isselected from the group consisting of: a telephone modern connectable toa circuit switched cellular means; a terrestrial cellular digital packetdata modern means; or, a digital satellite packet data modern means. 38.A system for sensing a characteristic at at least one remote locationand transferring data indicative of the sensed characteristic to a database located at a central location, remote from the remote location,said system comprising: at the remote location: a sensor for producing adigital output reading indicative of the sensed characteristic; memoryfor storing the digital output reading; a first communication unit forsending and receiving information to and from the remote location andthe central location; a processor for controlling the firstcommunication unit to send and receive information, controlling thesensor to produce the digital output reading and storing the digitaloutput reading in the memory; at the central location: a secondcommunication unit for sending and receiving information to and from thefirst communication unit at the remote location; a data base for storingdata received from the remote location; wherein the processor causes thedigital output readings to be stored in the memory until the digitaloutput reading can be transmitted to and received by the secondcommunication unit; and wherein the processor determines whether or notdata can be transmitted to and received by the second communication unitat the central location, and, controls the first communication unit tosend data corresponding to the digital output reading when the secondcommunication unit can receive the data.
 39. The system as defined inclaim 38 further comprising: an application protocol associated with thefirst communication unit and the second communication unit forfacilitating transfer of messages comprising the data and commands, toand from the remote location and the central location.
 40. The system asdefined in claim 39 wherein the application protocol performs at leastone of the functions of encryption, compression and decompression, andauthentication of the messages sent and received between the remotelocation and the central location.
 41. The system as defined in claim 38further comprising: a field instrument unit at the remote location, saidfield instrument unit housing the sensor, the memory, the firstcommunication unit and the processor.
 42. The system as defined in claim41 further comprising: a plurality of field instrument units, each fieldinstrument unit located at a separate remote location geographicallyseparated from each other for sensing characteristics at each of theremote locations and transferring data indicative of the sensedcharacteristics of the corresponding remote location to the data baselocated at the central location.
 43. The system as defined in claim 42where the processor of each of the plurality of field instrument unitscan process the digital output readings stored in the correspondingmemory of the field instrument unit; and wherein the processor of atleast one of the plurality of field instrument units processes thedigital output readings stored in its corresponding memory and transmitsto the central location processed digital output readings.
 44. Thesystem as defined in claim 42 wherein each of the plurality of fieldunits is located at an oil and gas facility which may be geographicallyseparated.
 45. The system as defined in claim 44 wherein the sensor ofeach field instrument unit senses pressure and temperature at the oiland gas facility where the field instrument unit is located; and whereinthe processor of at least one of the plurality of a field instrumentunits processes the digital output signals indicative of the pressure tocorrect for temperature errors based on the digital output signalsindicative of temperature and transmits to the central locationprocessed digital output readings.
 46. The system as defined in claims38 wherein: upon initial connection between the first communication unitand at the second communication unit, the processor sends and receivesinformation to the second communication unit to facilitate operation ofthe system.
 47. The system as defined in 38 wherein: after eachinterruption in the transmission of data to, or reception of data by,the second communication unit, the processor sends information to thesecond communication unit indicating that transmission of data has nowresumed and transmits data corresponding to the digital output readingswhich have been stored in the memory.
 48. The system as defined in claim42 wherein the plurality of field instrument units are arranged in astar topology with the database of the central location located at thecenter of the star topology.
 49. The system as defined in claim 48wherein the field instrument units and processors located at the centrallocation interchangeable act as servers and clients in the startopology.
 50. The system as defined in claim 39 wherein the firstcommunication unit and the second communication unit transmit andreceive messages using the application protocol over one or morenetworks selected from the group consisting of the Internet, PublicSwitch Telecommunication Network, Cellular Digital Packet Data andSatellite networks.
 51. The process as defined in claim 24 furthercomprising: after each interruption in the reception of data by thecommunication unit at the central location, automatically sending fiomthe remote location to the communication unit at the central locationinformation indicating that transmission of data has been resumed andsending data corresponding to the digital output readings which havebeen stored in the memory to the communication unit at the centrallocation.